In the past, a part called surface-mounted connector is known. The surface-mounted connector is a Part for providing removability to an electronic part to be mounted on a printed board. One of targets of application of the surface-mounted connector is an electronic part such as a different board, a semiconductor part or the like to be mounted on the printed board. The surface-mounted connector is hereinafter referred to simply as connector. The connector is suitable for use for collective mounting and dismounting of a plurality of conductors of an electronic part. Some of various connectors actually commercialized have a connector having electrodes of, for example, several tens to several hundreds of pins.
Generally, a great number of signal lines corresponding to electrodes are disposed in the inner side of the connector to be fixed to a printed board, and a lead is connected to an end of each signal line. The lead is fixed by solder to an electrode pad of the printed board and also the connector itself is fixed to the printed board.
incidentally, warping and unevenness of approximately several hundred [μm] to several [mm] exist on the surface of a printed board. Therefore, a gap sometimes appears between the electrode pad and the end of the lead when the connector is mounted on the printed board. Generally, solder is filled into such a gap as described above to secure bonding between the electrode pad and the lead.
However, in the case of a connector in which fine leads are disposed in high density, the area of the electrode pad on the printed board is set small and the solder amount for bonding the electrode pad and the lead is very small. Therefore, there is a subject that quality degradation and a bonding failure in solder bonding are likely to occur even if the distance between the electrode pad face and the end of the lead increases only a little.
Further, in a processor connector (socket) such as a PGA (Pin Grid Array), an LGA (Land Grid Array) or the like or a board connector whose bonded portion to a printed board is formed in a planar shape, an influence of warping is likely to be had in comparison with another connector in which leads are disposed in a row. Therefore, it is difficult to enhance the solder bonding performance of a lead.
Against such a subject as described above, a connector including a movable lead (adjustable lead) whose lead length can be adjusted has been developed. In particular, a slot is provided at an end portion of the connector along a signal line, and the movable lead is provided for sliding movement in the slot and is tacked to the signal line with solder paste. The tacked solder paste is melted upon reflowing, and the movable lead freely moves along the slot. Accordingly, the distance between the electrode pad face and the end of the movable lead can be changed while securing bonding between the movable lead and the signal line (for example, refer to U.S. Pat. No. 7,530,820).
However, in the connector described above, the movable lead is likely to contact with a wall of the slot and an operation failure of the movable lead by friction is likely to occur. Particularly, since a lead obtained from a lead frame formed by blanking (presswork) of a metal plate has an end face in the form of a rupture face, there is a subject that the lead is likely to catch on the slot wall and smooth sliding motion of the lead is likely to be obstructed.
On the other hand, it is also imaginable to form the slot wall sufficiently thicker than the lead in order to prevent contact between the lead and the slot wall. However, in this instance, since the disposing direction of the lead (direction in which the lead extends) and the direction of the lead face are not restricted by the slot wall, the lead is likely to be inclined with respect to the slot. In particular, the directions of leads projecting from the connector become irregular relative to each other, and consequently the quality of the solder bonding cannot be enhanced.